An electric motor-driven-type chainsaw having a saw chain configured to be driven and endlessly moved by an electric motor is known in the technical field of chainsaws. For example, JP 2015-074193 A discloses a chainsaw comprising an electric motor provided inside a housing, a guide bar, and a guide chain. The guide bar is provided in a front portion of the housing and protrudes forwardly therefrom. The saw chain is provided around an outer periphery of the guide bar in a tensioned state and is configured to be driven and endlessly moved by the electric motor. In this chainsaw, in a state in which the saw chain driven by the electric motor is endlessly moved along the outer periphery of the guide bar, the endlessly moved saw chain can be pressed against lumber or the like to cut the lumber or the like. This disclosed chainsaw comprises a side handle provided on a central portion of the housing, and a rear handle provided on a rear portion of the housing. A worker can carry out work of cutting lumber or the like while gripping both a handgrip in an upper portion of the side handle and a handgrip in an upper portion of the rear handle, for example, by using the worker's left hand and right hand, respectively. A trigger lever is swingably provided on a lower surface of the upper portion of the rear handle. The electric motor is configured to be activated by pulling the trigger lever toward the handgrip so as to perform a manipulation to an ON state.